Sergeant Derek Mooney (33), a member of the elite Army Ranger Wing, had been less than two weeks on United Nations peace-keeping duties when he lost his life in Liberia last November after his Land Rover 110 plunged off the road.

A native of Blackrock, Co Dublin, he had proposed to his long-term girlfriend Denise Kelleher just before he left Ireland to serve his country.

Circumstances surrounding the accident - which happened about 40km south of the capital of Monrovia on November 27 last - were outlined at Tallaght Coroner's Court yesterday.

Bertie Eggerton, a civilian who was travelling behind Sgt Mooney in the nine-vehicle convoy, told in a statement how he noticed a vehicle in front had "started to drift" towards the right-hand side of the road.

Attempts were made to bring the vehicle under control as it swerved from side to side, but it rolled over on to its and then on to its roof. Three people were lying on the ground, including Sgt Mooney.

A Liberian policeman at the scene told Mr Eggerton how people were always sliding off that part of the road as the surface was not 100pc coal tar but a mixture of different materials.

Evidence was also heard from the gunner in Sgt Mooney's vehicle. He said they were negotiating a left-hand bend when he "felt the wheels leaving the road". Sgt Mooney tried to correct the vehicle but it swerved sharply, started to tumble, rolled three times and came to a standstill.

In summing up, Dr Kieran Geraghty said: "No other vehicle was involved. This was a heavy, military vehicle with a gun on top. The wheel went over the edge of a bad road surface."

He described it as a "very sad accident" and said it was a tragic way for Sgt Mooney to die.

The jury recorded a verdict of accidental death and deepest sympathies were extended to the dead man's family.

* The specially modified and heavily armed Landrover 110s used by the Army Ranger Wing for long-range patrols in Liberia will shortly be replaced.

The vehicles will be stripped of their weapons and instead be used for training cross-country drivers.

However, the move is unrelated to the Liberian accident. An order for special reconnaissance vehicles based on the large American Ford F-350 4 x 4 vehicle, also heavily armed, was placed last September.